7. Frontend container

Now that we have a “backend”, why not deploy a frontend container (e.g. httpd & php) and make them speak to each other?

Deploying a frontend container

First thing: Find the fitting Docker image –> Where? Exactly… Docker Hub .

Use the php:8-apache image.

docker pull php:8-apache

Once it is pulled check your local docker images:

docker images

REPOSITORY          TAG                 IMAGE ID            CREATED             SIZE
php                 8-apache            41f84befd707        5 days ago          390MB
mariadb             latest              58730544b81b        2 weeks ago         397MB
hello-world         latest              1815c82652c0        2 months ago        1.84kB
hello-world         linux               1815c82652c0        2 months ago        1.84kB

This will show the images in the local registry with their name and tags.

By using docker pull php:8-apache Docker downloaded the php image with the 8-apache tag. If you omit the tag (so here docker pull php) docker would try to download the image with the latest tag.

For the hello-world image we see that we have the same image (read same image id) but two different tags (linux/latest).

Now deploy the new container using the correct tag:

docker run -d --name apache-php php:8-apache

docker ps shows all running containers. Check that apache-php is running:

docker ps

CONTAINER ID        IMAGE               COMMAND                  CREATED             STATUS              PORTS               NAMES
b901d6c0473a        php:8-apache        "docker-php-entryp..."   18 seconds ago      Up 17 seconds       80/tcp              apache-php
50197361e87b        mariadb             "docker-entrypoint..."   42 minutes ago      Up 42 minutes       3306/tcp            mariadb-container-with-existing-external-volume
6f08ac657320        mariadb             "docker-entrypoint..."   4 hours ago         Up 2 hours          3306/tcp            mariadb-container

Now, try to connect to the server using the container-assigned docker IP address:

Use the familiar command from lab 5:

docker inspect apache-php -f '{{ range.NetworkSettings.Networks }}{{ .IPAddress }}{{ end }}'

Which will show only the IP of the container as output:

172.17.0.4

With this IP navigate to the web server at http://172.17.0.4 .

docker stop apache-php
docker rm apache-php

docker run -p 8080:80 -d --name apache-php php:8-apache

Unfortunately we get a “403 Error - Forbidden”.

For now stop and remove this container:

docker stop apache-php
docker rm apache-php